S
M
T
W
T
F
S
30
62°
55°
31
63°
54°
1
64°
54°
2
64°
55°
3
63°
55°
4
63°
54°
5
64°
53°
6
62°
54°
7
67°
49°
8
63°
47°
9
64°
47°
10
63°
46°
11
62°
48°
12
63°
51°
13
62°
52°
14
68°
54°
15
68°
53°
16
64°
51°
17
66°
55°
18
66°
55°
19
64°
52°
20
67°
52°
21
67°
47°
22
63°
48°
23
62°
51°
24
62°
52°
25
61°
51°
26
64°
51°
27
64°
50°
28
62°
53°
29
66°
52°
30
64°
53°
1
67°
54°
2
69°
53°
3
68°
52°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Arcata
Arcata's September 2026 forecast shows daily high temperatures ranging from 61° to 69°, with overnight lows between 46° and 55°. The average high for September is 64° with an average low of 52°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how September weather will actually feel in Arcata. See also: October | November | December.
